#include <iostream>
#include <cmath>
using namespace std;

int main()
{
    int n, min1, min2, max1, max2, m, i;
    cin >> n;
    i = 1;
    max1 = -45000;
    max2 = -45000;
    min1 = 45000;
    min2 = 45000;
    while(i != n + 1)
    {
      cin >> m;
      if(m > max1)
      {
        max2 = max1;
        max1 = m;
      }
      else
      if(m > max2)
        max2 = m;
      if(m < min1)
      {
        min2 = min1;
        min1 = m;
      }
      else
      if(m <= min2)
      {
        min2 = m;
      }
      i++;
    }
    cout << min(max1 * max2, min1 * min2, max1 * min1);
    return 0;
}